A laparoscopic surgery is applied more and more widely. In order to avoid iatrogenic infection, the consumption of a disposable trocar used in the laparoscopic surgery is increasingly greater. The trend of simplifying the structure, reducing the cost, improving the performance on the basis of ensuring using performance has already become an improvement direction of the trocar.
In the prior art, the sealing of the trocar is formed by a radial sealing apparatus and an axial sealing apparatus.
A common axial sealing apparatus, namely, a check valve has many types. One type is a spring pressed check valve, forming sealing by a spring leaf pushing a flapper to oppress a silica gel sealing ring. The check valve is formed by the spring leaf, the flapper and the silica gel sealing ring. The spring leaf is made of stainless steel, and the flapper is made of medical plastics. The form of the axial sealing apparatus is usually used in a reusable trocar. In recent years, in order to adapt to the development requirement of the disposable trocar, a funnel-shaped silica gel sealing ring is developed. The funnel-shaped silica gel sealing ring has a straight through notch provided at the bottom of the funnel, and achieves the sealing effect by means of the contractility of the silica gel and the pressure formed by carbon dioxide pneumoperitoneum during use. The funnel-shaped silica gel sealing ring is generally widely used in the disposable trocar.
In the prior art, the radial sealing apparatus generally adopts a silica gel sealing ring of a funnel-shaped structure with a central hole, and the sealing ring easily leaks when a surgical instrument shakes, having a poor dynamic sealing effect. Particularly, when a 10 mm or 12 mm surgical instrument is inserted into a surgical instrument through hole of a sealing ring with the diameter being 4 mm, the resistance of the surgical instrument in reciprocating motion is large, which brings inconvenience to a surgical operation of a surgeon.
Surgical instruments have heads in different shapes. Particularly, a surgical instrument, such as a titanium clamp, having a V-shaped head splayed when being delivered to the abdominal cavity generally cannot pass through the sealing ring in the prior art, or may puncture the sealing ring in the prior art, thereby causing gas leakage. Another defect of the radial sealing apparatus in the prior art is that the type of the surgical instrument whose head has a groove or raised steps is easy to get stuck when the surgical instrument is removed, so the motion is not smooth.
Therefore, the radial sealing apparatus of the trocar in the prior art needs to be improved, so as to achieve the purpose of not only using a 10 mm surgical instrument on a trocar with the diameter being 10 mm, but also using surgical instruments with diameters between 5 mm and 10 mm; and not only using a 12 mm instrument on a trocar with the diameter being 12 mm, but also using surgical instruments with diameters between 5 mm and 12 mm, thereby being general. Meanwhile, the radial sealing apparatus of the improved trocar can be adapted to various surgical instruments in different shapes, thereby facilitating the insertion and removal of the instrument, with low resistance and smooth motion. Evidently, the sealing apparatus and the trocar in the prior art cannot satisfy the requirements, thus requiring improvement.